The hand is an intricately complex structure that is adapted to permit an unequalled array of movement. There are over sixty different muscles in the hand to accomplish this. The five metacarpal bones are the bones of what is considered the hand. The thumb and fingers are made of bones called phalanges and the bones create joints so that closing our hand is possible. The thumb has a proximal segment and a distal segment whereas the fingers or digits have a proximal, middle, and distal segment. Flexion and extension of the hand and phalanges or fingers are accomplished by extrinsic muscles of the hand (or those of forearm). Precise finger movements that require the coordination of abduction and adduction with flexion and extension are functionally the task of the small intrinsic (those inside) of the hand. The intrinsic muscles of the hand are divided into thenar (concerning palm on the thumb side) and hypothenar (concerning palm next to the little finger), and the intermediate groups.